Hello, i have an interresting topic today

C++ on solaris. lgpl stuff applicable.
My program is a deamon process wich takes input from network, then processes the data, and outputs reformatted to network. We're generating a lot of logging output. the logging is absolutely unbuffered at the moment like a log should be, fire and forget. (to a file ot STDOUT)

I cant run multiple process instances concurrently because there is no file locking implemented. I cant write to the same logfile from different processes. That means that i would end up with one logfile for each process. unusable.

problem:
I want to run multiple instances of the same process at the same time. The log output has to be in one logfile. The chunks wich are a unit must stay consectutive (there has to be buffer somewhere, i guess). And this i the only change i really want to commit to the existing program, 1 line in the code which tells when 1 "unit" is processed.I want as few changes as possible in the existing program.

How would you propose to achieve that?

i exclude all the "housekeeper process which concats all the generated logs once a day or sth." like ideas. This is crap.


And yeah the _MOST_ important thing.
My head is rolling if i lose 1 byte of logging output ever, under all circumstances. That means if you have ideas in client-server style (pipes sockets, shm, whatever) it has to be transactionoriented somehow.

I is an interresting problem, i greatly appreciate every creative idea!!!
Thanks folks!
Heck